Commit 22608405 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'for-5.3/dm-changes' of... 

Merge tag 'for-5.3/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Add encrypted byte-offset initialization vector (eboiv) to DM crypt.

 - Add optional discard features to DM snapshot which allow freeing
   space from a DM device whose free space was exhausted.

 - Various small improvements to use struct_size() and kzalloc().

 - Fix to check if DM thin metadata is in fail_io mode before attempting
   to update the superblock to set the needs_check flag. Otherwise the
   DM thin-pool can hang.

 - Fix DM bufio shrinker's potential for ABBA recursion deadlock with DM
   thin provisioning on loop usecase.

* tag 'for-5.3/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm bufio: fix deadlock with loop device
  dm snapshot: add optional discard support features
  dm crypt: implement eboiv - encrypted byte-offset initialization vector
  dm crypt: remove obsolete comment about plumb IV
  dm crypt: wipe private IV struct after key invalid flag is set
  dm integrity: use kzalloc() instead of kmalloc() + memset()
  dm: update stale comment in end_clone_bio()
  dm log writes: fix incorrect comment about the logged sequence example
  dm log writes: use struct_size() to calculate size of pending_block
  dm crypt: use struct_size() when allocating encryption context
  dm integrity: always set version on superblock update
  dm thin metadata: check if in fail_io mode when setting needs_check
parents 92adeb61 bd293d07

Documentation/device-mapper/snapshot.rst

+17 −1
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ its visible content unchanged, at least until the <COW device> fills up. 




-  snapshot <origin> <COW device> <persistent?> <chunksize>

   [<# feature args> [<arg>]*]



A snapshot of the <origin> block device is created. Changed chunks of

<chunksize> sectors will be stored on the <COW device>.  Writes will
@@ -54,8 +55,23 @@ When loading or unloading the snapshot target, the corresponding 
snapshot-origin or snapshot-merge target must be suspended. A failure to

suspend the origin target could result in data corruption.



Optional features:



* snapshot-merge <origin> <COW device> <persistent> <chunksize>

   discard_zeroes_cow - a discard issued to the snapshot device that

   maps to entire chunks to will zero the corresponding exception(s) in

   the snapshot's exception store.



   discard_passdown_origin - a discard to the snapshot device is passed

   down to the snapshot-origin's underlying device.  This doesn't cause

   copy-out to the snapshot exception store because the snapshot-origin

   target is bypassed.



   The discard_passdown_origin feature depends on the discard_zeroes_cow

   feature being enabled.





-  snapshot-merge <origin> <COW device> <persistent> <chunksize>

   [<# feature args> [<arg>]*]



takes the same table arguments as the snapshot target except it only

works with persistent snapshots.  This target assumes the role of the

drivers/md/dm-bufio.c

+1 −3
Original line number Diff line number Diff line
@@ -1599,9 +1599,7 @@ dm_bufio_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) 
	unsigned long freed;



	c = container_of(shrink, struct dm_bufio_client, shrinker);

	if (sc->gfp_mask & __GFP_FS)

		dm_bufio_lock(c);

	else if (!dm_bufio_trylock(c))

	if (!dm_bufio_trylock(c))

		return SHRINK_STOP;



	freed  = __scan(c, sc->nr_to_scan, sc->gfp_mask);

drivers/md/dm-crypt.c

+90 −11
Original line number Diff line number Diff line
@@ -120,6 +120,10 @@ struct iv_tcw_private { 
	u8 *whitening;

};



struct iv_eboiv_private {

	struct crypto_cipher *tfm;

};



/*

 * Crypt: maps a linear range of a block device

 * and encrypts / decrypts at the same time.
@@ -159,6 +163,7 @@ struct crypt_config { 
		struct iv_benbi_private benbi;

		struct iv_lmk_private lmk;

		struct iv_tcw_private tcw;

		struct iv_eboiv_private eboiv;

	} iv_gen_private;

	u64 iv_offset;

	unsigned int iv_size;
@@ -291,8 +296,9 @@ static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 
 *       Note that this encryption scheme is vulnerable to watermarking attacks

 *       and should be used for old compatible containers access only.

 *

 * plumb: unimplemented, see:

 * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454

 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)

 *        The IV is encrypted little-endian byte-offset (with the same key

 *        and cipher as the volume).

 */



static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
@@ -841,6 +847,67 @@ static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 
	return 0;

}



static void crypt_iv_eboiv_dtr(struct crypt_config *cc)

{

	struct iv_eboiv_private *eboiv = &cc->iv_gen_private.eboiv;



	crypto_free_cipher(eboiv->tfm);

	eboiv->tfm = NULL;

}



static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,

			    const char *opts)

{

	struct iv_eboiv_private *eboiv = &cc->iv_gen_private.eboiv;

	struct crypto_cipher *tfm;



	tfm = crypto_alloc_cipher(cc->cipher, 0, 0);

	if (IS_ERR(tfm)) {

		ti->error = "Error allocating crypto tfm for EBOIV";

		return PTR_ERR(tfm);

	}



	if (crypto_cipher_blocksize(tfm) != cc->iv_size) {

		ti->error = "Block size of EBOIV cipher does "

			    "not match IV size of block cipher";

		crypto_free_cipher(tfm);

		return -EINVAL;

	}



	eboiv->tfm = tfm;

	return 0;

}



static int crypt_iv_eboiv_init(struct crypt_config *cc)

{

	struct iv_eboiv_private *eboiv = &cc->iv_gen_private.eboiv;

	int err;



	err = crypto_cipher_setkey(eboiv->tfm, cc->key, cc->key_size);

	if (err)

		return err;



	return 0;

}



static int crypt_iv_eboiv_wipe(struct crypt_config *cc)

{

	/* Called after cc->key is set to random key in crypt_wipe() */

	return crypt_iv_eboiv_init(cc);

}



static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,

			    struct dm_crypt_request *dmreq)

{

	struct iv_eboiv_private *eboiv = &cc->iv_gen_private.eboiv;



	memset(iv, 0, cc->iv_size);

	*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector * cc->sector_size);

	crypto_cipher_encrypt_one(eboiv->tfm, iv, iv);



	return 0;

}



static const struct crypt_iv_operations crypt_iv_plain_ops = {

	.generator = crypt_iv_plain_gen

};
@@ -893,6 +960,14 @@ static struct crypt_iv_operations crypt_iv_random_ops = { 
	.generator = crypt_iv_random_gen

};



static struct crypt_iv_operations crypt_iv_eboiv_ops = {

	.ctr	   = crypt_iv_eboiv_ctr,

	.dtr	   = crypt_iv_eboiv_dtr,

	.init	   = crypt_iv_eboiv_init,

	.wipe	   = crypt_iv_eboiv_wipe,

	.generator = crypt_iv_eboiv_gen

};



/*

 * Integrity extensions

 */
@@ -2158,6 +2233,14 @@ static int crypt_wipe_key(struct crypt_config *cc) 


	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);

	get_random_bytes(&cc->key, cc->key_size);



	/* Wipe IV private keys */

	if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {

		r = cc->iv_gen_ops->wipe(cc);

		if (r)

			return r;

	}



	kzfree(cc->key_string);

	cc->key_string = NULL;

	r = crypt_setkey(cc);
@@ -2288,6 +2371,8 @@ static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 
		cc->iv_gen_ops = &crypt_iv_benbi_ops;

	else if (strcmp(ivmode, "null") == 0)

		cc->iv_gen_ops = &crypt_iv_null_ops;

	else if (strcmp(ivmode, "eboiv") == 0)

		cc->iv_gen_ops = &crypt_iv_eboiv_ops;

	else if (strcmp(ivmode, "lmk") == 0) {

		cc->iv_gen_ops = &crypt_iv_lmk_ops;

		/*
@@ -2699,7 +2784,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 
		return -EINVAL;

	}



	cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);

	cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);

	if (!cc) {

		ti->error = "Cannot allocate encryption context";

		return -ENOMEM;
@@ -3050,15 +3135,9 @@ static int crypt_message(struct dm_target *ti, unsigned argc, char **argv, 
				memset(cc->key, 0, cc->key_size * sizeof(u8));

			return ret;

		}

		if (argc == 2 && !strcasecmp(argv[1], "wipe")) {

			if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {

				ret = cc->iv_gen_ops->wipe(cc);

				if (ret)

					return ret;

			}

		if (argc == 2 && !strcasecmp(argv[1], "wipe"))

			return crypt_wipe_key(cc);

	}

	}



error:

	DMWARN("unrecognised message received.");
@@ -3094,7 +3173,7 @@ static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 


static struct target_type crypt_target = {

	.name   = "crypt",

	.version = {1, 18, 1},

	.version = {1, 19, 0},

	.module = THIS_MODULE,

	.ctr    = crypt_ctr,

	.dtr    = crypt_dtr,

drivers/md/dm-integrity.c

+4 −3
Original line number Diff line number Diff line
@@ -476,6 +476,9 @@ static int sync_rw_sb(struct dm_integrity_c *ic, int op, int op_flags) 
	io_loc.sector = ic->start;

	io_loc.count = SB_SECTORS;



	if (op == REQ_OP_WRITE)

		sb_set_version(ic);



	return dm_io(&io_req, 1, &io_loc, NULL);

}
@@ -2317,7 +2320,6 @@ static void recalc_write_super(struct dm_integrity_c *ic) 
	if (dm_integrity_failed(ic))

		return;



	sb_set_version(ic);

	r = sync_rw_sb(ic, REQ_OP_WRITE, 0);

	if (unlikely(r))

		dm_integrity_io_error(ic, "writing superblock", r);
@@ -3358,7 +3360,7 @@ static int create_journal(struct dm_integrity_c *ic, char **error) 
				goto bad;

			}



			crypt_iv = kmalloc(ivsize, GFP_KERNEL);

			crypt_iv = kzalloc(ivsize, GFP_KERNEL);

			if (!crypt_iv) {

				*error = "Could not allocate iv";

				r = -ENOMEM;
@@ -3387,7 +3389,6 @@ static int create_journal(struct dm_integrity_c *ic, char **error) 
				sg_set_buf(&sg[i], va, PAGE_SIZE);

			}

			sg_set_buf(&sg[i], &ic->commit_ids, sizeof ic->commit_ids);

			memset(crypt_iv, 0x00, ivsize);



			skcipher_request_set_crypt(req, sg, sg,

						   PAGE_SIZE * ic->journal_pages + sizeof ic->commit_ids, crypt_iv);

drivers/md/dm-log-writes.c

+2 −2
Original line number Diff line number Diff line
@@ -40,7 +40,7 @@ 
 *

 * Would result in the log looking like this:

 *

 * c,a,flush,fuad,b,<other writes>,<next flush>

 * c,a,b,flush,fuad,<other writes>,<next flush>

 *

 * This is meant to help expose problems where file systems do not properly wait

 * on data being written before invoking a FLUSH.  FUA bypasses cache so once it
@@ -699,7 +699,7 @@ static int log_writes_map(struct dm_target *ti, struct bio *bio) 
	if (discard_bio)

		alloc_size = sizeof(struct pending_block);

	else

		alloc_size = sizeof(struct pending_block) + sizeof(struct bio_vec) * bio_segments(bio);

		alloc_size = struct_size(block, vecs, bio_segments(bio));



	block = kzalloc(alloc_size, GFP_NOIO);

	if (!block) {

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